Royal Mail Large Letter Size Boxes

If you are looking for postal cardboard boxes that specifically fall into and meet the Royal Mail Large Letter size category then you are in the right place. All of our brown and white cardboard boxes listed here are specifically large letter postal boxes. We have a huge range of different sized Large Letter cardboard boxes which go right up to the Royal Mail PiP (Pricing In Proportion) limit.

We have carefully checked & ensured that all the external sizes of our cardboard boxes fit into the Royal Mail Large Letter category. Please note where the external dimensions of a box are particularly close to the Large Letter limit, extra care should be taken when constructing, packing & franking the box to ensure you do not accidentally go over that limit. No responsibility can be taken by Mailcoms Ltd should your box be charged by your post office at a higher rate than the one stated by Royal Mail for a Large Letter item.